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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549



                                    FORM 8-K

                                 CURRENT REPORT

     PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934




        Date of report (date of earliest event reported): April 21, 2003




                         MARTIN MIDSTREAM PARTNERS L.P.
             (Exact name of Registrant as specified in its charter)


<Table>
<S>                         <C>                                   <C>
       DELAWARE                   000-50056                                   05-0527861
(State of incorporation     (Commission file number)              (I.R.S. employer identification number)
    or organization)

                    4200 STONE ROAD
                    KILGORE, TEXAS                                               75662
       (Address of principal executive offices)                                (Zip code)
</Table>



       Registrant's telephone number, including area code: (903) 983-6200

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ITEM 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS.

         (c)      EXHIBITS

         Pursuant to the rules and regulations of the Securities and Exchange
Commission, the attached exhibit is deemed to have been furnished pursuant to

Item 9 and should not be deemed to be "filed" under the Securities Exchange Act
of 1934.


<Table>
<Caption>
           EXHIBIT
           NUMBER                  DESCRIPTION
           -------                 -----------
<S>                                <C>
           99.1          --        Press release dated April 21, 2003.
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ITEM 9. REGULATION FD DISCLOSURE.

         On April 21, 2003, Martin Midstream Partners L.P. (the "Partnership")
issued a press release announcing that on May 15, 2003 it will pay a minimum
quarterly distribution of $0.50 per unit to its common and subordinated
unitholders of record as of the close of business on May 2, 2003. A copy of the
press release is furnished as an exhibit to this Current Report. Pursuant to the
rules and regulations of the Securities and Exchange Commission, such exhibit
and the information set forth therein is deemed to have been furnished and shall
not be deemed to be "filed" under the Securities Exchange Act of 1934.



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                                   SIGNATURES

         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.


                                          MARTIN MIDSTREAM PARTNERS L.P.

                                          By:   Martin Midstream GP LLC
                                          Its:  General Partner


Date: April 21, 2003               By: /s/ RUBEN S. MARTIN
                                      ------------------------------------------
                                      Ruben S. Martin
                                      President and Chief Executive Officer




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                                INDEX TO EXHIBITS


<Table>
<Caption>
EXHIBIT
NUMBER                 DESCRIPTION
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<S>                    <C>
99.1             --    Press release dated April 21, 2003.
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                         MARTIN MIDSTREAM PARTNERS L.P.
                        TO PAY QUARTERLY DISTRIBUTION ON
                                  May 15, 2003


         KILGORE, Texas, April 21, 2003/PRNewswire-FirstCall via COMTEX/--Martin
Midstream Partners L.P. (Nasdaq: MMLP) announced today that is has declared a
cash distribution of $0.50 per unit, payable on May 15, 2003 to common and
subordinated unitholders of record as of the close of business on May 2, 2003.
Based on current operating conditions, MMLP anticipates that it will fully pay
minimum quarterly distributions of $0.50 per common and subordinated unit for
all quarterly periods through December 31, 2003.

About Martin Midstream Partners

         Martin Midstream Partners provides marine transportation, terminalling,
distribution and midstream logistical services for producers and suppliers of
hydrocarbon products and by-products, specialty chemicals and other liquids. The
Company also manufactures and markets sulfur-based fertilizers and related
products and owns an unconsolidated non-controlling 49.5% limited partnership
interest in CF Martin Sulphur L.P., which operates a sulfur storage and
transportation business. MMLP operates primarily in the Gulf Coast region of the
United States.

         Additional information concerning
 the Company is available via the
worldwide web at http://www.martinmidstream.com.

Forward-Looking Statements

         Statements about Martin Midstream Partners' outlook and all other
statements in this release other than historical facts are forward-looking
statements within the meaning of the Private Securities Litigation Reform Act of
1995. These forward-looking statements and all references to financial estimates
rely on a number of assumptions concerning future events and are subject to a
number of uncertainties and other factors, many of which are outside its
control, that could cause actual results to differ materially from such
statements. While MMLP believes that the assumptions concerning future events
are reasonable, it cautions that there are inherent difficulties in anticipating
or predicting certain important factors. These factors include, but are not
limited to: adverse weather conditions; reliance on its interest in CF Martin
Sulphur L.P.; the incurrence of material liabilities that are not fully covered
by insurance; the price volatility and the supply availability of hydrocarbon
products and by-products; restrictions in its debt agreements; the prospects for
future acquisitions and its ability to make future acquisitions; the performance
of recently acquired businesses; the seasonality of its business; the
competition in the industry; changes in regulations on the federal, state and
local level that are applicable to its business; the cost of attracting and
retaining highly skilled personnel; the loss of significant commercial
relationships with Martin Resource Management Corporation; interruption in
operations at its facilities; federal regulations applicable to its marine
vessels and regulations effecting the domestic tank vessel industry; cost
reimbursements it is required to pay to Martin Resource Management Corporation;
conflicts of interest and competition with Martin Resource Management
Corporation; the decisions made by and the control of its general partner; and a
decision by the IRS to treat MMLP as a corporation. A discussion of these
factors, including risks and uncertainties, is set forth from time to time in
the Company's filings with the Securities and Exchange Commission. Martin
Midstream Partners L.P. disclaims any intention or obligation to revise any
forward-looking statements, including financial estimates, whether as a result
of new information, future event, or otherwise.

Contact: Robert D. Bondurant, Executive Vice President and Chief Financial
Officer of Martin Midstream GP LLC (903) 983-6200